Johannes Kepler certainly lived in interesting times in the sense of the old Chinese curse. Born 27th December 1571 he lived through the most intensive phase of the Counter-Reformation being forced, as a Protestant living and working in Catholic territory, to abandoned his home and livelihood more than once. Trained as a Luther priest he served three Catholic Holy Roman Kaisers as mathematicus and the supreme commander of the Catholic forces in the thirty years war as an astrologus. Always walking along a knife-edge. The last twelve years of his life were dominated by that most devastating of European wars. He played a very central role in one of the greatest upheavals in the history of astronomy as well as redefining the science of physical optics. He lost his first wife and several of his children to sickness and was chronically and oft acutely ill all of his life. Paid at best on an irregular basis by his various employers he was often in desperate need of money. He also lived during the highpoint of the European witch craze in which tens of thousands of innocent people, mostly women, were persecuted, tortured and murdered and must experience how his own mother was tried for practicing witchcraft. All in all if a Hollywood scriptwriter were to write a screenplay outlining the life of Johannes Kepler it would probably be turned down by the producers as too fantastic.

I think of all the misfortunes that Kepler battled with in his life probably the most extraordinary was the accusation of witchcraft against his mother. Beginning in 1615 as a spat between neighbours this affair hung over the heads of the entire Kepler family until its final resolution in October of 1621. Initially Ursula Reinbold a neighbour and ex-friend of Kepler’s mother, Katharina, accused the old lady of having poisoned her with a magic potion following a business dispute. In the atmosphere of the witch craze an accusation of witchcraft formed the basis of a very potent smear campaign. Later in the same year a cousin of Reinbold’s and the local magistrate, a friend of the family, whilst drunk, tried to force Katharina at sword point to admit that she was a witch. Following this episode Katharina brought a civil suit for slander against the Reinbold family. From this point on the situation spiralled out of control. Einhorn, the magistrate aware that he could be in serious trouble because of his sword swinging drunken escapade successfully blocked the civil process from coming to trial over the next four years whilst simultaneously constructing a spurious case against Katharina based on rumour and hearsay. Einhorn was aided in his efforts by the fact that Katharina was, according to Kepler’s own description, anything but a pleasant woman, meaning that there were plenty of people more than prepared to speak ill of her and also by the fact that she made the strategic mistake of trying to bribe the magistrate at one point in the proceedings.

In December 1616 Kepler tried to defuse the situation by obtaining permission from the Duke of Württemberg, who because Kepler had received a state grant to finance his education whilst still a youth remained his lifelong liege lord, to remove his mother out of the firing line in Württemberg and take her to his home in Linz. If Katharina had been content to stay with her famous son in Austria then she would probably have remained unmolested for the rest of her life. However she was a stubborn and cantankerous old battle-axe and determined to confront her accuser and so late in 1617 she returned home to do just that. Things took their course and in August 1620 following years of legal wrangling Katharina Kepler was arrested and imprisoned on forty-nine formal charges of practicing witchcraft.

Kepler travelled back to Württemberg and alongside the attorney he had engaged for his mother he personally took charge of her defence. The original prosecutor so in awe of the powerful defence team being arranged against him, highly unusual in a witchcraft trial, had the whole process moved to a higher court. Finally after much more legal wrangling the prosecution and the defence submitted their final statements. The final statement for the defence was a closely argued logical structured 128-page demolition of the prosecutions case largely written by Kepler himself. The whole case was now passed on the law faculty of the University of Tübingen, Kepler’s Alma Mater, who decided that Katharine should be taken to the hangman and shown the instruments of torture and ordered to confess. On 21st October 1621 this was duly carried out but the stubborn old lady refused to bend she said,

“Do with me what you want. Even if you were to pull one vein after another out of my body, I would have nothing to admit.” Then she fell to her knees and said a Pater Noster. God would she said, bring the truth to light and after her death disclose that wrong and violence had been done to her. He would not take the Holy Ghost from her and would stand by her.

[Max Casper, Kepler, Trans & Ed C. Doris Hellman, 1959 p. 255]

The Duke now declared that having suffered this ordeal and not confessed she had confounded the evidence against her and should be set free, which she duly was as soon as Johannes had paid the court costs.

One interesting aspect of the modern versions of this story is that all the authors assume and indeed emphasise that Katharine was entirely innocent of the charges against her and that she was the victim of a malicious plot carried out by the Reinholds and Einhorn the local magistrate. Whilst this point of view does have a lot of validity it is not totally correct. It was obvious from his writings that Kepler was convinced that his mother was indeed a witch. She earned at least part of her income peddling magical potions. The modern writers declare these to be simple peasant herbal cures but it is clear that these potions owed their supposed efficacy to charms or magic spells that Katharine had learnt from her own mother and that this knowledge of the arcane was what her clients were paying for. Katharine’s reputation of a purveyor of spells and charms certainly worked against her when her enemies were constructing their case against her.

When I decided to write about Kepler’s mother and her trial for witchcraft in my annual Kepler Christmas post this year I took the opportunity to finally read James A. Connor’s Kepler’s Witch: An Astronomer’s Discovery of Cosmic Order Amid War, Political Intrigue, and the Heresy Trial of His Mother, which I bought some time ago. I wish I hadn’t! The book is a biography climaxing with the story of Katharine’s witchcraft trial. Connor starts by explaining that he wishes to concentrate on the biography and will therefore be leaving the science out of the story. Writing a biography of Kepler without the science is like making whiskey sours without the whiskey! However it is not possible so Connor does includes brief descriptions of Kepler’s scientific activities. I wish he hadn’t! He has literally no idea what he’s talking about and the results are pitiful. I have no desire to relive the whole horror but I was fascinated to discover that before Kepler wrote his Dioptrice (1611) telescopes only had one lens! It is not only in terms of science that Connors displays strange interpretations of history. When discussing the causes of the witch craze he explains that it was due to the ignorant superstition of peasants in small towns and villages. The role played by the churches doesn’t exist in Connor’s historical vision and the mass trials and executions that took place in the large towns and cities are also apparent non-existent in Connor’s universe. I discovered what I consider to be the worst sin in Connor’s book purely by accident. He plagiarises massively. To check some of the claims he was making I controlled them against the English translation of Max Casper’s Kepler, the standard biography. I was surprised as I discovered a whole paragraph in Connor’s text that was word the word the same as a paragraph in the Casper’s text. I then started to check systematically and discovered quite a lot of similar identical passages. Conclusion, if you were thinking of buying or reading Connor’s book don’t bother read the Casper’s instead it’s at least a hundred times better

“that it was due to the ignorant superstition of peasants in small towns and villages.”

The source material he cites at the start of the book, i.e Kepler’s letter from January 1616 to the Senate of Leonberg. is a standard text book example of elite interaction (with popular culture) almost from start to finish; references to elite belief in satanic pact (the basis for prosecution in Europe at the period) etc.

At a loss to understand his perspective and interpretation of source material.